package common.filter;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.filter.OncePerRequestFilter;

public class SessionFilter extends OncePerRequestFilter {

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.springframework.web.filter.OncePerRequestFilter#doFilterInternal(
	 * javax.servlet.http.HttpServletRequest,
	 * javax.servlet.http.HttpServletResponse, javax.servlet.FilterChain)
	 */
	@Override
	protected void doFilterInternal(HttpServletRequest request,
			HttpServletResponse response, FilterChain filterChain)
			throws ServletException, IOException {
		// 不过滤的uri
		String[] notFilterLike = new String[] { "toCompleteRetailer",
				"completeRetailer", "toLogin", "/login", "/logout",
				"retailer_css", "retailer_js", "validate_js", "/inc",
				"/script", "toRegedit", "regedit", "home", "css", "file","/static","/ckeditor","android",
				"/main", "images" };
		String[] notFilterEqual = new String[] { "/" };
		// 请求的uri
		String uri = request.getRequestURI();

		// 是否过滤
		boolean doFilter = true;
		for (String s : notFilterLike) {
			if (uri.indexOf(s) != -1) {
				// 如果uri中包含不过滤的uri，则不进行过滤
				doFilter = false;
				break;
			}
		}
		for (String s : notFilterEqual) {
			if (uri.equals(s)) {
				// 如果uri中包含不过滤的uri，则不进行过滤
				doFilter = false;
				break;
			}
		}
		if (doFilter) {
			// 执行过滤
			// 从session中获取登录者实体
			Object user_obj = request.getSession().getAttribute("user");
			Object retailer_obj = request.getSession().getAttribute("retailer");
			if (null == user_obj && null == retailer_obj) {
				// 如果session中不存在登录者实体，则弹出框提示重新登录
				// 设置request和response的字符集，防止乱码
				request.setCharacterEncoding("UTF-8");
				response.setCharacterEncoding("UTF-8");
				PrintWriter out = response.getWriter();
				String loginPage = "/admin/toLogin";
				StringBuilder builder = new StringBuilder();
				builder.append("<script type=\"text/javascript\">");
				builder.append("alert('网页过期，请重新登录！');");
				builder.append("window.top.location.href='");
				builder.append(loginPage);
				builder.append("';");
				builder.append("</script>");
				out.print(builder.toString());
			} else {
				// 如果session中存在登录者实体，则继续
				filterChain.doFilter(request, response);
			}
		} else {
			// 如果不执行过滤，则继续
			filterChain.doFilter(request, response);
		}
	}

}